Line of credit facility interest-only period.

No definition available.

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Namespace Prefix:	stim_
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Balance Type:	na
Period Type:	duration

- Definition

Line of credit facility interest only period extension upon achievement of revenues.

+ References

No definition available.

+ Details

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Namespace Prefix:	stim_
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Balance Type:	na
Period Type:	duration

- Definition

Number of default events.

+ References

No definition available.

+ Details

Name:	stim_NumberOfDefaultEvents
Namespace Prefix:	stim_
Data Type:	xbrli:integerItemType
Balance Type:	na
Period Type:	duration

- Definition

Term loans number of tranches.

+ References

No definition available.

+ Details

Name:	stim_TermLoansNumberOfTranches
Namespace Prefix:	stim_
Data Type:	xbrli:integerItemType
Balance Type:	na
Period Type:	duration

- Definition

Percentage points added to the reference rate to compute the variable rate on the debt instrument.

+ References

No definition available.

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	duration

- Definition

The reference rate for the variable rate of the debt instrument, such as LIBOR or the US Treasury rate and the maturity of the reference rate used, such as three months or six months LIBOR.

+ References

No definition available.

+ Details

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- Definition

The carrying value as of the balance sheet date of the current and noncurrent portions of long-term obligations drawn from a line of credit, which is a bank's commitment to make loans up to a specific amount. Examples of items that might be included in the application of this element may consist of letters of credit, standby letters of credit, and revolving credit arrangements, under which borrowings can be made up to a maximum amount as of any point in time conditional on satisfaction of specified terms before, as of and after the date of drawdowns on the line. Includes short-term obligations that would normally be classified as current liabilities but for which (a) postbalance sheet date issuance of a long term obligation to refinance the short term obligation on a long term basis, or (b) the enterprise has entered into a financing agreement that clearly permits the enterprise to refinance the short-term obligation on a long term basis and the following conditions are met (1) the agreement does not expire within 1 year and is not cancelable by the lender except for violation of an objectively determinable provision, (2) no violation exists at the BS date, and (3) the lender has entered into the financing agreement is expected to be financially capable of honoring the agreement.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02(22))
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 210
-Section S99
-Paragraph 1
-Subparagraph (SX 210.9-03(16))
-URI http://asc.fasb.org/extlink&oid=6876686&loc=d3e534808-122878

Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 944
-SubTopic 210
-Section S99
-Paragraph 1
-Subparagraph (SX 210.7-03(16))
-URI http://asc.fasb.org/extlink&oid=119400593&loc=d3e572229-122910

+ Details

Name:	us-gaap_LineOfCredit
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

Description of the credit facility's borrowing capacity including discussion of how the borrowing capacity is determined (for example, borrowing capacity based on the amount of current assets).

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02(22)(b))
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

Reference 2: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02(19)(b))
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

- Definition

Description of the conditions for borrowing under the credit facility including the nature of any restrictions.

+ References

+ Details

Name:	us-gaap_LineOfCreditFacilityCovenantTerms
Namespace Prefix:	us-gaap_
Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

- Definition

Maximum borrowing capacity under the credit facility without consideration of any current restrictions on the amount that could be borrowed or the amounts currently outstanding under the facility.

+ References

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

Detail information of subsequent event by type. User is expected to use existing line items from elsewhere in the taxonomy as the primary line items for this disclosure, which is further associated with dimension and member elements pertaining to a subsequent event.

+ References

No definition available.

+ Details

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Period Type:	duration

- Details

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- Details

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Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_VariableRateAxis=stim_IntercontinentalExchangeBenchmarkAdministrationLtdMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_CreditFacilityAxis=stim_ThirtyFiveMillionCreditFacilityMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_DebtInstrumentAxis=stim_TermALoanMember
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Balance Type:
Period Type:

- Details

Name:	us-gaap_DebtInstrumentAxis=stim_TermBLoanMember
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Data Type:	na
Balance Type:
Period Type:

- Details

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Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

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Balance Type:
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- Details

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- Details

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Subsequent Events - Additional Information (Details)		12 Months Ended
Subsequent Events - Additional Information (Details)	Mar. 02, 2020 USD ($) Tranche Event	Dec. 31, 2019 USD ($)	Mar. 31, 2017 USD ($)	Feb. 28, 2017 USD ($)
Subsequent Event \| Term A Loan and Term B Loan
Subsequent Event [Line Items]
Basis spread on variable rate	1.66%
Interest-only period	2022-03
Interest-only period upon achievement of revenues	2023-02
Number of default events \| Event	0
Line of credit facility, conversion to term loan, conditions	At the Company’s election, the interest only period may be extended through February 2023 if the Company satisfies a minimum net product revenue covenant through March 1, 2022 and no event of default shall have occurred.
Subsequent Event \| Term A Loan and Term B Loan \| Intercontinental Exchange Benchmark Administration Ltd
Subsequent Event [Line Items]
Basis spread on variable rate	7.65%
Debt instrument, description of variable rate basis	one month plus 7.65%
$35.0 Million Credit Facility \| Term A Loan
Subsequent Event [Line Items]
Interest-only period		2019-03
Interest-only period upon achievement of revenues		2020-03
$35.0 Million Credit Facility \| Term B Loan
Subsequent Event [Line Items]
Interest-only period		2019-03
Interest-only period upon achievement of revenues		2020-03
$35.0 Million Credit Facility \| Oxford Finance LLC
Subsequent Event [Line Items]
Line of credit facility, maximum borrowing capacity			$ 35,000,000	$ 25,000,000
Borrowings outstanding under credit facility		$ 30,000,000
$35.0 Million Credit Facility \| Oxford Finance LLC \| Term A Loan
Subsequent Event [Line Items]
Borrowings outstanding under credit facility			25,000,000
$35.0 Million Credit Facility \| Oxford Finance LLC \| Term B Loan
Subsequent Event [Line Items]
Borrowings outstanding under credit facility			$ 5,000,000
$35.0 Million Credit Facility \| Solar Capital Ltd \| Subsequent Event \| Term A Loan
Subsequent Event [Line Items]
Borrowings outstanding under credit facility	$ 35,000,000
$50.0 Million Credit Facility \| Solar Capital Ltd \| Subsequent Event
Subsequent Event [Line Items]
Line of credit facility, maximum borrowing capacity	$ 50,000,000
Term loans number of tranches \| Tranche	2
$15 Million Credit Facility \| Solar Capital Ltd \| Subsequent Event \| Term B Loan
Subsequent Event [Line Items]
Line of credit facility, maximum borrowing capacity	$ 15,000,000
Line of credit facility, conversion to term loan, conditions	Subject to certain conditions, under the Term B Loan portion of the Solar Facility, the Company is permitted to borrow, at its election, up to an aggregate amount of $15.0 million, (i) upon the Company’s achieving a trailing twelve month net product revenue milestone, and (ii) assuming no event of default shall have occurred prior to such election.